[Feature Request] set pk column after columns creation

[kcmvp]

when create columns with CreateColumnsOf as below, there is no way to set a PK field.

` obj := map[string]any{ "name": "Roman", "age": 35, "wallet": 50.99, "health": 100, "mana": 200, }

col := NewCollection()
col.CreateColumnsOf(obj)`

if there is a new API such as collection.setPK(colName string) then we can set an existing column as PK. Of course, this api only available when the collection is emtpy.

[kelindar]

I'm actually thinking of removing this API altogether, to keep overall API simple and more consistent. Maybe we can consider creating an "ORM" package for column that can auto-create column schemas off maps, structs etc. 🤔